This acoustic investigation focuses on the preservation of the two low French vowels /a/ vs. /&#593;/ within a vowel system that otherwise manifests striking convergent properties with English. Our acoustic data demonstrate that this inherited contrast is preserved, with a distribution largely reflective of conservative French, despite various pressures on our speakers that might cause them to alter their phonetic categories in a language contact situation (in the sense of Flege 1987). The larger picture that emerges is that in contact situations we observe a complex pattern of transfer versus maintenance that cannot be accounted for via any of the current models of bilingual phonology – models driven by language internal pressures such as level differences between phonology and phonetics, sound similarity, functional load, or universal statements of markedness.